Atherosclerosis, or hardening of the arteries, leads to blocked arteries, says Michael Wood, MD, a cardiothoracic surgeon at MountainView Hospital. In this video, he describes symptoms of blocked arteries.

Blocked arteries can cause heart attacks, strokes and other serious problems. But what exactly goes wrong? How do arteries become blocked to begin with?

Each artery is made up of three layers: a smooth layer on the inside, a thick layer of muscle in the middle and a rough layer on the outside. Your arteries are strong and flexible, but they can become less effective over time. The smooth inner lining of the artery can become damaged, causing a substance called plaque to build up or blood to start clotting at the injury site. Plaque is made up of fat, cholesterol, calcium and scar tissue. The risk of plaque formation in the arteries is increased by several factors:

Saturated fats and trans fats in the diet

Cholesterol in the diet

Diabetes

High blood pressure (hypertension)

Genetics (family history)

Smoking

Plaque and blood clots inhibit blood flow in the arteries and can ultimately stop or block it altogether. Controlling risk factors such as diet can help stop, slow or sometimes even reverse the blockage of arteries.

Your circulatory system is made up of your heart, blood, blood vessels and lungs. In your circulatory system your heart pumps blood transporting nutrients, water and oxygen to your bodys cells. Your circulatory system allows your lungs to rid the body of waste and carbon dioxide and bring oxygen into your blood.
Exercise and healthy eating are two ways you can help keep your circulatory system healthy. Smoking does damage to healthy blood circulation. When you smoke the carbon monoxide and nicotine entering your body have negative effects on your blood and blood vessels and constrict circulation.
Signs of poor circulation include cold hands and feet, numbness, dizziness, migraines, varicose veins and pain in your feet or legs. Consult a doctor if you have these symptoms. Untreated, poor circulation can lead to stroke, high blood pressure, kidney damage and other diseases.